JPS6038025Y2 - Intake device for generating swirl in direct injection engines - Google Patents

Description

[Detailed description of the invention] The present invention relates to an intake system that sucks air while creating a swirl in a direct injection engine, and the invention uses the same parts to achieve excellent fuel performance for both high-speed and low-speed engines. The purpose is to make engines easy to manufacture at low cost.

When high output is required, a high-speed rotation engine is used, and when rotation stability, stickiness, durability, etc. are required, a low-speed rotation engine is used.

In direct injection engines, the strength of the intake air swirl has a large effect on fuel performance.

In order to improve combustion performance, in high-speed engines, the swirl tends to become too strong in proportion to the intake speed, so the intake passage is formed in such a way that swirl is less likely to occur, and in low-speed engines, the swirl tends to be too strong. Since the intake air tends to be insufficient, it is necessary to form the intake passage in such a way that swirl is likely to occur.

For this reason, conventionally, it has not been possible to share parts between high-speed engines and low-speed engines, resulting in high manufacturing costs.

This invention allows both high-speed and low-speed engines to be manufactured easily and inexpensively using exactly the same parts, while still maintaining high combustion performance by giving each engine the optimum swirl characteristics. To this end, an intake pipe is attached to an intake port formed to generate a swirl so that its angle can be adjusted, and the strength of the swirl can be adjusted by adjusting the angle.

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows an overall side view of a horizontal water-cooled diesel engine. This engine E has a radiator 2 and a fuel tank 3 arranged on the left and right above a crankcase 1, and
A cylinder head 4 is fixed to the left side of a crankcase 1.

This cylinder head 44 covers the upper end of the cylinder 5 installed inside the crankcase 1, and forms a combustion chamber 7 between it and the upper surface of a piston 6 that is slidably provided in the cylinder 5.

The combustion chamber 7 is configured as a so-called direct injection engine in which a fuel injection nozzle 8 inserted and fixed from the outside of the cylinder head 4 directly faces the combustion chamber 7 .

The cylinder head 4 is formed with an intake port 9 and an exhaust port (not shown) that communicate with the combustion chamber 7, and each port 9 is connected to and from an intake valve (2) and an exhaust valve (not shown).

This intake port 9, as shown in FIGS. 3 and 4,
An intake pipe 10 is connected to and connected to the intake pipe 9a, and a swirling force is applied to the intake air sucked into the combustion chamber 7, thereby forming a swirl.

Then, the intake pipe 10 is angled with respect to the axial direction 11 of the cylinder 5 so that the swirl formed in the combustion chamber 7 is formed in the most ideal state according to the normal rotational speed of the engine E. 12 so that the angle can be adjusted.

That is, as shown in FIG. 2, the angle adjusting means 12 forms a mounting part 13 for the intake pipe 10 on the peripheral wall 9b of the inlet 9a of the intake port 9 formed in the cylinder head 4. 14, and the stud bolt (fixing means) 14 is attached to the flange 1 of the terminal end 10a of the intake pipe 10.
After passing through a long hole 16 for angle adjustment provided in 5, it is fixed with a nut (fixing means) 17.

In this way, by making the angle of the intake pipe 10 adjustable with respect to the axial direction 11 of the cylinder 5, when the normal operating speed of the engine E is low, the intake pipe 10 can be adjusted in the axial direction 11 of the cylinder 5. It is fixed in an upright state so that it forms a large angle θ1 with respect to the main body.

Then, as the piston 6 descends, the intake air sucked into the combustion chamber 7 from the intake pipe 10 is directed so as to generate a large amount of swirl in the combustion chamber 7, as shown by dotted line A, but since the descending speed of the piston 6 is low, The swirl formed in the combustion chamber 7 is not excessive, and the best swirl is formed in the low speed rotation range.

Conversely, in the case of engine E, which has a high normal rotational speed, intake pipe 1
0 with respect to the axial direction 11 of the cylinder 5,
It is attached at a small angle θ2.

Then, the intake air drawn into the combustion chamber 7 has a reduced number of revolutions in the combustion chamber 7, as shown by the two-dot chain line B, but the piston 6
Since the downward speed of the air is fast and the suction speed of intake air is fast, an appropriate swirl can be obtained with strong suction inertia, and there will be no excess or deficiency of swirl.

Incidentally, reference numeral 18 indicates an intake pipe 10 consisting of a display mark 19 engraved on the mounting portion 13 of the cylinder head 4 and an alignment mark 20 provided around the elongated hole 16 of the flange portion 15 of the intake pipe 10. This is a mounting angle display device.

Since the present invention is configured and operates as described above, it can be manufactured easily and inexpensively using exactly the same parts for both high-speed and low-speed engines, while still adjusting the installation angle of the intake pipe. This allows each engine to have the optimum swirl characteristics and maintain high combustion performance.

In addition, by changing the installation angle of the intake pipe, it is possible to switch from a high-speed engine to a medium-speed engine or a low-speed engine for efficient operation. It can also be used by switching to a standard engine.

[Brief explanation of the drawing]

Figure 1 is a schematic side view of a direct injection type water-cooled horizontal diesel engine, Figure 2 is a side view of the main parts to explain the operation, and Figure 3 is a side view of the main parts of the engine.
The figure is a sectional view taken along the line ■--■ in FIG. 2, and FIG. 4 is a perspective view of the intake port portion. E...Engine, 5...Cylinder, 9
...Intake port, 9a...Inlet of 9,
9b...peripheral wall of 9a, 10...intake pipe, 10a...terminal end of 10, 12...
Angle adjustment means, 13...Mounting part, 14°17.
...Fixing means (14...planting holt, 1
7...Natsuto).

Claims (1)

[Scope of utility model registration request] The intake pipe 10 is connected smoothly and continuously to the inlet 9a of the swirl-generating intake port 9 of the direct injection engine E, and the terminal end 10a of the intake pipe 10 is connected to the mounting part 13 of the peripheral wall 9b of the inlet 9a of the intake port 9. The fixing means 14.17 allows the angle to be adjusted in the axial direction 11 of the cylinder 5 by the angle adjusting means 12.
An intake device for generating a swirl for a direct injection engine, which is characterized by being fixed with.